Proponents of International Paretianism (IP)—the principle that international agreements should not make any state worse off and should make some at least better off—argue that it is the only feasible approach to reducing the harms of climate change. They draw on some key assumptions regarding the meaning of ‘feasibility’ and the nature of the Pareto improvements associated with coordinated action on climate change. This chapter challenges these assumptions, in effect weakening the case for IP and allowing for broader thinking about what counts as a ‘feasible’ climate solution.